Project Description: Immigrant populations, by virtue of being medically-underserved, low-income, and of race-/ethnic and linguistic minority status are at particularly high risk to become obese as they adapt to the obesogenic environment in which they reside once in the US. Preventive interventions developed with the active participation of these communities have the potential to prevent or moderate the weight gain. We will demonstrate, using measures of effectiveness, the feasibility of partnering with the immigrant community in Somerville, MA to refine, implement, evaluate, and disseminate a 2-year preventive intervention to moderate or reduce weight gain in 435 mother/child dyads of new immigrants. The 435 mother/child dyads will be randomized to either receive the intervention or to serve as controls that will receive a delayed intervention, once the main trial is completed. We will enroll immigrants from Brazil, Haiti, and Latin-American countries, groups who are coming in large numbers to eastern MA, and are served by local community agencies. Intervention targets focus on 10 family-based goals in the areas of healthy eating, increased physical activity, and the reduction of sedentary behavior. Specifically, the intervention is designed to bring adults into the healthy weight range by reducing or maintaining BMI by providing education, skill development and support. In children it will be designed to result in an increased energy expenditure of up to 125 kcals per day beyond the increases in energy expenditure and energy intake that accompany growth. Based on our formative research within these groups, intervention elements will be delivered in small groups at the agencies of our community partners. }Lifestyle coaching} sessions and support groups tailored to the specific immigrant groups'needs will capitalize on traditional healthy behaviors practiced by new immigrants and teach specific strategies that effect family environments. The proposed project reflects the ongoing work of a multidisciplinary research group and builds on two successful research initiatives in Somerville, one completed and one ongoing. The goals of this community-based participatory research study have been developed from community interest and involvement. The community partners engaged with us to conduct the formative research used to develop this application, and will be involved in the design, recruitment, delivery, and research evaluation throughout the project. Dissemination of results to the affected community was deemed critical and will be done with the intention of strengthening community resources, preventive health care and education for immigrants. Furthermore, if successful, national dissemination of this trial can assist other communities with large immigrant populations to reduce the risk of obesity in this vulnerable population. PUBLIC HEALTH RELEVANCE: New immigrants to the US are at high risk of weight gain and obesity as they adapt to their new obesogenic environment. Our tailored intervention, developed with active input of our community partners, stands to benefit long-term health, in the prevention of heart disease, diabetes, and some cancers, and thereby reduce burgeoning health care costs.